I have one of those, teeter ups brand i think.

It was a novelty around here for a while, then it got moved to the garage, now it's at phase 3...piled up outside the garage beside other junk and headed to the recycler for what little weight in steel it contributes to my trailer full of waah machines and water heaters.

I really hate that, I paid $300 for it 20 yrs ago.

My back hurts enough now, I'd almost go scrub the tree sap off of it and try.

My chiropractor and neurologist both told me not use it. Said it might give me an anuerysm. lol